1. Field of the Invention
The present invention relates to a projector type vehicle light employing an LED (light emitting diode) as the light source for use as a headlamp in a vehicle.
2. Description of the Related Art
FIG. 1 shows a conventional projector type vehicle light 100 which is disclosed in Japanese Utility model Application Laid-Open No. Hei-6-41010 (Application No. Hei-4-76322). The vehicle light 100 comprises a light source bulb 2 provided close to the primary focusing point of a concave mirror 1 and a convex lens 3 for modulating the flux of light emitted from the light source bulb 2 and reflected by the concave mirror 1 to substantially a parallel light which is then directed towards the front.
More specifically, the vehicle light 100 has a shade 4 provided between the light source bulb 2 and the convex lens 3 for projecting a desired cut-line pattern of light selectively used when the vehicle passes through another.
The light source bulb 2 has a filament located at the primary focusing point of the concave mirror 1 and an electric connection fitted into a tubular opening 1a thereof. A frame 5 is mounted to the opening end of the concave mirror 1 and arranged to which the convex lens 3 is fixedly joined and supporting the shade 4.
The vehicle light 100 also has a ventilation through hole 1b and ventilation through holes 1c provided therein just above and below the tubular opening 1a of the concave mirror 1 respectively where the light source bulb 2 is installed, as best shown in FIG. 2.
When the vehicle light 100 is lit, its temperature will increase about the light source bulb 2, however, since the heat generated is emitted out by the effect of thermal convection between the through holes 1b and 1c, temperature rising about the light source bulb 2 can be suppressed.
However, the vehicle light 100 has a disadvantage that while the light source bulb 2 releases an output of light at higher thermal energy, the convex lens 3 has to be made of a glass material thus increasing the overall weight.
Also in the vehicle light 100, while the convex lens 3 is made of glass, the concave mirror 1 is made of an aluminum vapor deposited sheet, a resin sheet, or a steel sheet, the shade 4 is made of an aluminum vapor deposited sheet or a steel sheet, and the frame 5 is made of an aluminum vapor deposited sheet. Since the components of the vehicle light 100 are made of different materials, they have to be fabricated separately before assembled together. Also, the assembly process may however be troublesome in which the light axis to be set at higher precision is deviated from the designed requirement due to variations in the assembly dimensions as well as the component dimensions. As a result, the lighting performance may be declined.
Moreover, as the number of its components is not small, the vehicle light 100 will be intricate in the component management, increased in the number of assembling steps, and not reduced in the overall cost.
As having been in service, the concave mirror 1 in the vehicle light 100 may be declined at the center area in the reflectivity where the through holes 1b and 1c are provided. Accordingly, the hot zone at the center of the pattern of light emission will be declined in the intensity.
The vehicle light 100 also permits the pattern of light emission to be released in one single mode, whereby the lighting can hardly be modified delicately depending on the condition of a road, the information of a map, and/or the running speed of the vehicle.
For example, a spot of intensified light is desired during the running at high speeds while dim lighting without spotting is preferable in a town. When the vehicle runs at a curve, its lighting along the curve will be desired with the spot of light shifting from left to right or vice versa.